Answer:
Oxygen is oxidized and hydrogen is reduced.
Explanation:
Let's consider the redox reaction during the electrolysis of water in an electrolytic cell.
2 H₂O ⇒ 2 H₂ + O₂
The corresponding half-reactions are:
2 e⁻ + 2 H₂O ⇒ H₂ + 2 OH⁻
2 H₂O ⇒ O₂ + 4 H⁺ + 4 e⁻
Oxygen is oxidized since its oxidation number increases from -2 to 0.
Hydrogen is reduced since its oxidation number decreases from +1 to 0.
Answer:
1370moles
Explanation:
Given parameters:
Number of molecules in methane = 8.25 x 10²⁶molecules
Unknown:
Number of moles of methane = ?
Solution:
A mole of any substance contains the Avogadro's number of particles which is 6.02 x 10²³molecules;
6.02 x 10²³ molecules is contained in 1 mole of a substance
8.25 x 10²⁶molecules of methane will contain = 1370moles
Answer:
8.9x10¹⁷ atoms of Al are present
Explanation:
To find the number of atoms from the mass of an atom we must convert, as first, the mass to moles using the molar mass of the atom (26.98g/mol For Aluminium).
Then, we must convert the moles to atoms knowing that 1mol = 6.022x10²³ atoms.
<em>Moles Aluminium:</em>
4.0x10⁻⁵g * (1mol / 26.98g) = 1.483x10⁻⁶ moles Al
<em>atoms:</em>
1.483x10⁻⁶ moles Al * (6.022x10²³ atoms / mol) =
<h3>8.9x10¹⁷ atoms of Al are present</h3>
The appropriate initial step when you design an experiment is number (2). It is doing research about the problem utilizing information from different reliable sources. Among all the choices, this is the first step that should be done because you have to know everything about the problem first before the other 3 steps are done.